Seat apparatus

ABSTRACT

A seat apparatus includes a vehicle seat including a cushion member having a bottom portion with a plurality of recessed portions, a plurality of air cells configured to expand by injection of compressed air, and a fluid supply mechanism configured to supply the fluid to the air cells. In the seat apparatus, at least one of the recessed portions is provided at a portion of the bottom portion of the cushion member positioned at a seating portion of the vehicle seat, the hip of a passenger being placed on the seating portion. Each air cell is expandable in a corresponding one of the recessed portions. The fluid supply mechanism is configured to expand at least one air cell by supplying the compressed air thereto and to change the at least one air cell to be expanded by switching a fluid supply destination.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/403,754, filed May 6, 2019, now U.S. Pat. No. 10,696,203, which is acontinuation of U.S. patent application Ser. No. 15/354,272, filed Nov.17, 2016, now U.S. Pat. No. 10,279,719, which claims the prioritybenefit of Japanese Patent Application Nos. JP2015-226976, filed Nov.19, 2015 and JP2016-203700, filed Oct. 17, 2016, the contents of allbeing incorporated herein by reference.

BACKGROUND

The present disclosure relates to a seat apparatus, and particularlyrelates to a seat apparatus capable of ensuring both of elasticity andhardness of a vehicle seat.

A vehicle seat is typically configured such that a cushion member iscovered with a skin material. Moreover, the cushion member is formed ofa relatively-soft material, such as urethane foam, so that a favorableride quality can be provided to a passenger of a vehicle. Note that alower hardness of the cushion member results in a greater change inelasticity of the seat over time, and therefore, lowering of suchelasticity is easily accelerated.

There is a vehicle seat configured such that an air cushion is providedat a position below a cushion member for the purpose of adjustinghardness of the vehicle seat (see, e.g., Japanese Patent Publication JP2005-125861). According to the vehicle seat described in JP 2005-125861,compressed air is injected into the air cushion to expand the aircushion, and therefore, hardness of the seat can be set to a properhardness. Thus, lowering of elasticity of the vehicle seat can besuppressed.

As described above, it has been demanded for a vehicle seat that both ofelasticity and hardness are ensured as performance of the vehicle seat.In addition to the above-described demand, it has been demanded that thestate of the vehicle seat is smoothly switched, and more specifically,is smoothly switched depending on the situation between the state ofstably holding a passenger's posture and the state of not interrupting aposture change.

A flow path for supplying compressed air to a bag body such as theabove-described air cushion is sometimes made of a bendable material(hereinafter referred to as a “flow path formation member”) such as afilm. In such a configuration, when the flow path formation member isinvoluntarily bent, the flow path is clogged, and as a result, supply ofcompressed air to the air cushion and discharge of compressed air fromthe air cushion might not be properly performed.

Moreover, in a configuration in which electric equipment operating tosupply compressed air is housed in a seat, a portion of a cushion memberof the seat may be recessed such that a housing space is provided, forexample. In this configuration, there is a possibility that foreignsubstances, rainwater, etc. having entered the housing space interferewith operation of the electric equipment.

SUMMARY

The present disclosure has been made in view of the above-describedproblems, and an embodiment provides a seat apparatus capable ofensuring both of elasticity and hardness (e.g., firmness) of a vehicleseat and properly switching a state of the vehicle seat depending onvarious situations. Moreover, an embodiment of the present disclosurereduces clogging of a flow path due to bending of a flow path formationmember in a configuration in which the flow path formation member is abendable material. Further, an embodiment of the present disclosuresuppresses foreign substances, rainwater, etc. from entering a housingspace for electric equipment in a configuration in which a portion of acushion member of a seat is recessed such that the housing space isprovided.

Some of the above-described problems are solved by an embodiment of aseat apparatus of the present disclosure. Such an embodiment of a seatapparatus includes a vehicle seat including a cushion member having abottom portion with a plurality of recessed portions, a plurality of bagbodies configured to expand by injection of fluid, and a fluid supplymechanism configured to supply the fluid to the bag bodies. Some of therecessed portions are provided in a portion of the bottom portion of thecushion member positioned in a seating portion of the vehicle seat, theseating portion being a portion of the vehicle seat on which a hip of aseated passenger is placed. Each bag body is expandable in acorresponding one of the recessed portions. The fluid supply mechanismis configured to expand at least one bag body of the plurality of thebag bodies by supplying the fluid thereto and to change the at least onebag body to be expanded by switching a fluid supply destination.

In the seat apparatus of the present disclosure configured as describedabove, the recessed portions are provided at the bottom portion of thecushion member of the vehicle seat. With such recessed portions, thecushion member easily bends along the shape of the hip of the passengerwhen the passenger is seated on the vehicle seat. Moreover, the bag bodyconfigured to expand by injection of the fluid is disposed in eachrecessed portion. Thus, hardness is ensured by the expanded bag bodies.That is, in an embodiment of the seat apparatus of the presentdisclosure, both of elasticity and hardness of the vehicle seat areensured. Of the plurality of bag bodies provided in an embodiment of theseat apparatus of the present disclosure, the bag bodies to be expandedcan be changed. With this configuration, the hardness of the vehicleseat can be locally adjusted. That is, in an embodiment of the seatapparatus of the present disclosure, a cushion member portion whosehardness is increased can be changed depending on the situation. As aresult, in an embodiment of the seat apparatus of the presentdisclosure, the state of the vehicle seat can be properly switcheddepending on the situation.

Moreover, in an embodiment of the above-described seat apparatus, therecessed portions formed at the portion of the bottom portion of thecushion member positioned at the seating portion are provided such thata distance between adjacent ones of the plurality of the recessedportions is uniform. In the above-described configuration, the recessedportions are equally provided at the bottom portion of the cushionmember. In such a configuration, the flexibility of the cushion membercan be further improved.

Further, in an embodiment of the above-described seat apparatus, each ofthe plurality of bag bodies includes two or more expandable portionsarranged with a dividing portion being interposed therebetween, the bagbodies are arranged such that a distance between adjacent ones of thebag bodies is uniform, and internal spaces of the two or more expandableportions of the each of the plurality of the bag bodies communicate witheach other. In the above-described configuration, the bag bodiescommunicate with each other, and each bag body has such a structurewhere two or more expandable portions are arranged with the dividingportion being interposed therebetween. With such a structure, two ormore expandable portions expand along the arrangement direction thereof,and therefore, the expansion direction of each bag body is suitablycontrollable. Moreover, the bag bodies are equally arranged, andtherefore, the hardness of the vehicle seat is adjustable with afavorable balance in partial hardness adjustment.

In addition, in an embodiment of the above-described seat apparatus,each bag body may be an air cell, and the air cell may be configured toexpand along the thickness direction of the vehicle seat by injection ofcompressed air as the fluid and to contract in the thickness directionby discharging of the injected compressed air. In the above-describedconfiguration, the air cell is used as the bag body. The air cell isconfigured to expand/contract in the thickness direction of the vehicleseat. With such a configuration, the hardness of the vehicle seat can beadjusted by a relatively-lightweight simple structure.

Moreover, in an embodiment of the above-described seat apparatus, two ormore of the bag bodies are coupled together, and internal spaces of thetwo or more coupled bag bodies communicate with each other. In theabove-described configuration, some of the bag bodies are coupledtogether. Thus, the coupled bag bodies can be collectively handled, and,e.g., the process for attaching the bag bodies is further facilitated.

Further, in an embodiment of the above-described seat apparatus, thefluid supply mechanism may include a switching device operating toswitch the fluid supply destination, a sensor configured to output asignal corresponding to a traveling condition of a vehicle on which thevehicle seat is mounted, and a control device configured to control theswitching device according to the signal output from the sensor, and thecontrol device may control the switching device to switch the at leastone bag body to be expanded. Of the plurality of bag bodies, the bagbodies to be expanded are, in the above-described configuration,switched according to the traveling condition of the vehicle. With thisconfiguration, a hardness balance at the vehicle seat can be optimizedaccording to the traveling condition of the vehicle.

In addition, in an embodiment of the above-described seat apparatus, thebag bodies include air cells. The fluid supply mechanism includes acompressed air generation device configured to generate compressed airas the fluid, a supply path formation member forming a supply path ofthe compressed air, and the switching device connected to the supplypath formation member and operating to switch the compressed air supplydestination. The air cells, the compressed air generation device, andthe switching device may be attached to the bottom portion of thecushion member. In the above-described configuration, the air cells asthe bag bodies and the components of the fluid supply mechanism areattached to the cushion member to form a unit. With this configuration,the air cells and each component of the fluid supply mechanism can bemore easily handled.

Moreover, in an embodiment of the above-described seat apparatus, thecompressed air generation device and the switching device are attachedto a portion of the bottom portion of the cushion member at a positiondifferent from the seating portion. In the above-describedconfiguration, the compressed air generation device and the switchingdevice are arranged at the portion of the vehicle seat at the positiondifferent from the seating portion, and therefore, influence of thesedevices on a ride quality can be reduced.

Further, an embodiment of the above-described seating device includes aflow path formation member including a flow path formed for the fluid toextend toward each bag body and made of a bendable material, and atubular body disposed in the flow path formation member and forming, onan inner side thereof, a portion of the flow path. In an embodiment, thetubular body is made of a material harder than the material of the flowpath formation member. In the above-described configuration, the tubularbody made of the material harder than that of the flow path formationmember is disposed in the flow path formation member made of thebendable material. With this configuration, bending of the flow pathformation member can be controlled by the tubular body, and clogging ofthe flow path due to bending of the flow path formation member can bereduced.

In addition, in an embodiment of the above-described seating device, theflow path is connected to each bag body, and at least a portion of thetubular body is, in the flow path formation member, disposed at aconnection portion between the flow path and each bag body. In theabove-described configuration, at least the portion of the tubular bodyis, in the flow path formation member, disposed at the connectionportion between the flow path and the bag body. The connection portionbetween the flow path and the bag body allows for proper expansionand/or contraction of the bag body. Thus, the tubular body disposed atsuch a portion can be more effectively utilized.

Moreover, in an embodiment of the above-described seating device, aportion of the flow path formation member in which the tubular body isdisposed includes a raised portion raised along a surface of the tubularbody and positioned to face the cushion member, and a flat portionpositioned opposite to the raised portion and extending flat. In theabove-described configuration, the portion of the flow path formationmember in which the tubular body is disposed has the raised portion andthe flat portion, and the flat portion is positioned opposite to thecushion member (in other words, positioned on the same side as a cushionmember support member such as a bottom plate). That is, the portion ofthe flow path formation member in which the tubular body is disposedcontacts, at a flat surface, the cushion member support member such asthe bottom plate. Thus, the portion of the flow path formation member inwhich the tubular body is disposed receives a load applied from acushion member support member side. As a result, damage (or breaking) ofthe flow path formation member due to the above-described load can bereduced.

Further, in an embodiment of the above-described seating device, thetubular body is made of a resin material identical to that of the flowpath formation member, and is welded to the flow path formation member.In addition, in the above-described seating device, each bag body andthe flow path formation member may be integrally made of a commonmaterial.

Moreover, in an embodiment of the above-described seating device, thefluid supply mechanism includes electric equipment operating to supplythe fluid. In an embodiment, the bottom portion of the cushion member isprovided with a housing space of the electric equipment, and the housingspace is formed by recessing a portion of the bottom portion. In anembodiment, a cover member configured to cover at least a portion of anopening of the housing space is further provided. In the above-describedconfiguration, the recessed housing space configured to house theelectric equipment is formed at the bottom portion of the cushionmember, and the opening of the housing space is covered with the covermember. Thus, adherence of foreign substances, rainwater, etc. to theelectric equipment in the housing space is reduced.

Further, in an embodiment of the above-described seating device, thecushion member may include an inclined portion inclining with respect tothe thickness direction of the vehicle seat. The bottom portion at theinclined portion may be provided with a cavity, and the cavity is formedby recessing a portion of the bottom portion. The cavity may becontinuous to the housing space. The cover member may cover the openingof the housing space in the state in which at least a portion of anopening of the cavity opens. In the above-described configuration, thehousing space of the electric equipment and the cavity formed at thebottom portion of the inclined portion of the cushion member arecontinuous to each other. Moreover, the cover member covers the openingof the housing space in the state in which at least the portion of theopening of the cavity opens. With these configurations, ventilation tothe housing space can be ensured while adherence of foreign substances,rainwater, etc. to the electric equipment can be reduced. Moreover, evenif rainwater enters the housing space, such rainwater can be properlydischarged through the opening of the cavity.

According to an embodiment of the present disclosure, both of theelasticity and hardness of the vehicle seat can be ensured, and thestate of the vehicle seat can be properly switched depending on thesituation. Moreover, according to an embodiment of the presentdisclosure, the recessed portions are equally provided at the bottomportions of the cushion member, and therefore, the flexibility of thecushion member can be further improved. Further, according to anembodiment of the present disclosure, each bag body expands along thearrangement direction of two expandable portions, and therefore, theexpansion direction can be properly controlled. In addition, the bagbodies are equally arranged, and therefore, the hardness of the vehicleseat can be adjusted with the favorable balance in partial hardnessadjustment. In addition, according to an embodiment of the presentdisclosure, the air cell is used as the bag body, and therefore, thehardness of the vehicle seat can be adjusted by therelatively-lightweight simple structure. Moreover, according to anembodiment of the present disclosure, some of the bag bodies are coupledtogether, and therefore, handling of these bag bodies is furtherfacilitated. Further, according to an embodiment of the presentdisclosure, the bag bodies to be expanded are switched according to thetraveling condition of the vehicle, and therefore, the hardness balance(hardness distribution) at the vehicle seat can be optimized accordingto the traveling condition of the vehicle. In addition, according to anembodiment of the present disclosure, the air cells as the bag bodiesand the components of the fluid supply mechanism are attached to thecushion member to form the unit, and therefore, handling of each of theabove-described components is further facilitated. Moreover, accordingto an embodiment of the present disclosure, the compressed airgeneration device and the switching device are arranged at the positiondifferent from the seating portion in the vehicle seat, and therefore,influence of these devices on the ride quality can be reduced. Further,according to an embodiment of the present disclosure, clogging of theflow path due to bending of the flow path formation member can bereduced. In addition, according to an embodiment of the presentdisclosure, the tubular body is disposed at the significantly importantportion in proper expansion/contraction of the bag body, and therefore,the tubular body can be more effectively utilized. Moreover, accordingto an embodiment of the present disclosure, when the load is appliedfrom, e.g., the bottom plate to the portion of the flow path formationmember in which the tubular body is disposed, damage (or breaking) ofthe flow path formation member due to such a load can be reduced.Further, according to an embodiment of the present disclosure, adherenceof foreign substances, rainwater, etc. to the electric equipment in thehousing space formed at the bottom portion of the cushion member can bereduced. In addition, according to an embodiment of the presentdisclosure, ventilation to the housing space can be ensured whileadherence of foreign substances, rainwater, etc. to the electricequipment in the housing space can be reduced. Moreover, even ifrainwater enters the housing space, such rainwater can be properlydischarged.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the invention are illustrated in the drawings, inwhich:

FIG. 1 is a perspective view of an example vehicle seat of an embodimentof the present disclosure;

FIG. 2 is a schematic side view of an outer appearance of an example aircell, according to an embodiment;

FIG. 3 is a block diagram of an example fluid supply mechanismconfiguration, according to an embodiment;

FIG. 4 is a perspective view of a compressed air generation device, aswitching device, and a supply path formation member, according to anembodiment;

FIG. 5 is a perspective view of a cushion member of the vehicle seat,according to an embodiment;

FIG. 6 is a schematic cross-sectional view of the vehicle seat,according to an embodiment;

FIG. 7 is a bottom view of a bottom portion of the cushion member,according to an embodiment;

FIG. 8 is a bottom view of arrangement positions of the air cells, thecompressed air generation device, and the switching device, according toan embodiment;

FIG. 9 is a schematic cross-sectional view for describing operation ofthe air cell, according to an embodiment;

FIG. 10 is a schematic plan view of air cells, according to anembodiment;

FIG. 11 is an example flowchart of a hardness adjustment flow, accordingto an embodiment;

FIG. 12 is a bottom view of a bottom portion of the cushion member,illustrating a first mode of the modes for expanding the air cells,according to an embodiment;

FIG. 13 is a bottom view of the bottom portion of the cushion member,illustrating a second mode of the modes for expanding the air cells,according to an embodiment;

FIG. 14 is a bottom view of the bottom portion of the cushion member,illustrating a third mode of the modes for expanding the air cells,according to an embodiment;

FIG. 15 is a schematic view of a bottom portion of a cushion member andvarious types of equipment disposed on the bottom portion, according toan embodiment;

FIG. 16 is a plan view of an air cell unit, according to an embodiment;

FIG. 17 is an exploded, perspective view of the air cell unit, accordingto an embodiment;

FIG. 18A is a side, schematic view of an assembly step of the air cellunit (No. 1), according to an embodiment;

FIG. 18B is a side, schematic view of another assembly step of the aircell unit (No. 2), according to an embodiment;

FIG. 18C is a side, schematic view of still another assembly step of theair cell unit (No. 3), according to an embodiment;

FIG. 19A is an enlarged, partial schematic view of a region X of FIG.16, according to an embodiment;

FIG. 19B is a schematic cross-sectional view along an X-X line of FIG.19A, according to an embodiment; and

FIG. 20 is a cross-sectional view of a vehicle seat of the variationalong an A-A line of FIG. 15, according to an embodiment.

DETAILED DESCRIPTION

An embodiment of a seat apparatus (the present embodiment) of thepresent disclosure is described below. Moreover, a seat apparatusmounted on a motorcycle is described below as an example. Note that theseat apparatus of the present disclosure can be mounted on vehiclesother than the motorcycle in other embodiments, such as vehiclesincluding, e.g., a motor tricycle and an automobile, or can be mountedon ships and airplanes. The seat apparatus of the present disclosure isparticularly effective in a vehicle seat on which a passenger of avehicle is seated with the passenger straddling the seat, i.e., in avehicle including a saddle ride type seat.

Note that in the description below, a “front-to-back direction”corresponds to the front-to-back direction of a vehicle seat 1, and is adirection parallel with the traveling direction of the motorcycle.Moreover, a “width direction” corresponds to the width direction (thehorizontal width) of the vehicle seat 1, and is a direction parallelwith a right-to-left direction when the motorcycle is viewed from afront side. Unless otherwise provided, the position, movement, etc. ofvarious types of equipment described below are those when the motorcycleis in a generally upright state (e.g., a state in which the motorcycleis not horizontally inclined with respect to the ground).

General Configuration of Seat Apparatus

First, a general configuration of the seat apparatus (hereinafterreferred to as a “present device 100”) of the present embodiment isdescribed. The present device 100 includes, generally, the vehicle seat1 illustrated in FIG. 1, air cells 20 illustrated in FIG. 2, and a fluidsupply mechanism 30 illustrated in FIGS. 3 and 4. FIG. 1 is aperspective view of the vehicle seat 1 of the present embodiment. FIG. 2is a schematic side view of an outer appearance of the air cell 20. FIG.3 is a block diagram of the configuration of the fluid supply mechanism30. FIG. 4 is a perspective view of an air supply pump 31, a valve unit32, and tubes 33 as components of the fluid supply mechanism 30.

The passenger of a motorcycle (e.g., the vehicle) is seated on thevehicle seat 1, and the vehicle seat 1 is used in the state in which thevehicle seat 1 is attached to a seat mount portion of a motorcycle body(a vehicle body). Each air cell 20 is a bag body used for adjustment ofthe hardness (e.g., firmness) of the vehicle seat 1, and is configuredto expand by injection of compressed air as a fluid. The fluid supplymechanism 30 is configured to supply the compressed air to the air cells20.

In the present device 100, the air cells 20 and the fluid supplymechanism 30 are built in the vehicle seat 1, and a mountain pass roadswitch 36 (described below) is attached to a predetermined portion(e.g., a handle portion) of the vehicle seat 1. Specifically, the aircells 20 and the fluid supply mechanism 30 are attached to a cushionmember 2 (the cushion member 2 is described below) in the vehicle seat1. As described above, in the present embodiment, the vehicle seat 1,the air cells 20, and the fluid supply mechanism 30 are integrated as aunit. Thus, the present device 100 can be handled as a single unit. Thatis, the present device 100 can be easily attached in such a manner thatthe vehicle seat 1 including the air cells 20 and the fluid supplymechanism 30 is only attached to the motorcycle body.

Note that the method for attaching each of the air cells 20 and thefluid supply mechanism 30 to the cushion member 2 is not limited, andeach of the air cells 20 and the fluid supply mechanism 30 may beattached with an adhesive or with a ready-made fastener, for example.

Components of the Seat Apparatus

A configuration example of each of the vehicle seat 1, the air cells 20,and the fluid supply mechanism 30 as the components of the presentdevice 100 is now described.

The vehicle seat 1 is a saddle ride type seat as illustrated in FIG. 1,and a general configuration of the vehicle seat 1 is similar to that ofa typical vehicle seat. Specifically, the vehicle seat 1 is configuredsuch that the cushion member 2 illustrated in FIG. 5 is, as illustratedin FIG. 6, covered with a skin material 4 with the cushion member 2being placed on a bottom plate 3. FIG. 5 is a perspective view of thecushion member 2. FIG. 6 is a schematic cross-sectional view of thevehicle seat 1, and illustrates a cross section along an A-A line ofFIG. 5.

The cushion member 2 is a member defining the outer shape of the vehicleseat 1, and is formed of a soft foam material. Urethane foam,polypropylene foam, or polyethylene foam can be utilized as the foammaterial.

The vehicle seat 1 of the present embodiment is a seat for two persons,the seat including seating portions 1 a, 1 b at front and back endportions of the seat. The seating portions 1 a, 1 b are portions of thevehicle seat 1 on which the hips of the passengers are placed. That is,front and back end portions of the cushion member 2 form hip supportportions 2 a, 2 b. The hip support portions 2 a, 2 b are portions of thecushion member 2 positioned respectively in the seating portions 1 a, 1b.

A non-seating portion 1 c on which no passenger is seated is providedbetween the front seating portion 1 a and the back seating portion 1 bat the vehicle seat 1. That is, a non-supporting portion 2 c positionedat the non-seating portion 1 c is provided between the front hip supportportion 2 a and the back hip support portion 2 b in the front-to-backdirection of the cushion member 2. The non-supporting portion 2 c is aportion of the cushion member 2 different from the seating portions 1 a,1 b.

Note that the non-seating portion 1 c has a step, and the step forms aback rest configured to support the waist of the passenger seated on thefront seating portion 1 a. Thus, at the cushion member 2, the back hipsupport portion 2 b is provided at a position higher than the front hipsupport portion 2 a by the above-described step.

A bottom portion 2 x of the cushion member 2 has a plurality of recessedportions 10 as illustrated in FIGS. 6 and 7. FIG. 7 is a bottom view ofthe bottom portion of the cushion member 2 when the cushion member 2 isviewed from below. The recessed portions 10 is described in detailbelow.

Each recessed portion 10 is a substantially hemispherical or ovalrecess. As illustrated in FIG. 6, a lower end of each recessed portion10 is an open end. Moreover, as illustrated in this figure, an upper endof each recessed portion 10 is positioned slightly lower than an upperend surface (i.e., a surface receiving a load from the passenger(s)) ofthe cushion member 2 in the thickness direction of the cushion member 2.

As illustrated in FIG. 7, the recessed portions 10 are formed at equalintervals across substantially the entirety of the bottom portion 2 x ofthe cushion member 2. That is, the bottom portion 2 x at each of thefront hip support portion 2 a, the back hip support portion 2 b, and thenon-supporting portion 2 c are provided with the recessed portions 10such that the distance (indicated by a character “d” in FIG. 7) betweenadjacent ones of the recessed portions 10 is uniform.

A formation pattern of the recessed portions 10 in the presentembodiment is described with reference to FIG. 7. In a line at thecenter of the bottom portion 2 x of the cushion member 2 in the widthdirection, seven recessed portions 10 are arranged in line along thefront-to-back direction. In each line at the side of the center line,seven recessed portions 10 are arranged along the front-to-backdirection. In each line on a further outer side in the width direction,five recessed portions 10 are arranged in the front-to-back direction.

The formation position of each recessed portion 10 in the line at thecenter of the bottom portion 2 x of the cushion member 2 in the widthdirection shifts, by a predetermined distance, in the front-to-backdirection from the formation position of a corresponding one of therecessed portions 10 in the lines at the side of the center line.Moreover, the formation position of each recessed portion 10 in theoutermost lines in the width direction at the bottom portion 2 x of thecushion member 2 also shifts, by the predetermined distance, in thefront-to-back direction from the formation position of a correspondingone of the recessed portions 10 in adjacent lines of the outermostlines. As described above, in the present embodiment, the lines of therecessed portions 10 are formed in the width direction, and the recessedportions 10 of these lines are arranged in a zigzag pattern. That is,the recessed portions 10 in each line are formed respectively atpositions shifted (e.g., offset) in the front-to-back direction and thewidth direction from the recessed portions 10 in adjacent lines.

As described above, the recessed portions 10 are formed at the bottomportion 2 x of the cushion member 2, and therefore, the weight of thecushion member 2 is further reduced. Moreover, since the recessedportions 10 are formed at the bottom portion 2 x of the cushion member2, the cushion member 2 can receive a load from the passenger(s) tofavorably bend when the passenger(s) is seated on the vehicle seat 1.The above-described effect of improving the flexibility of the cushionmember 2 is more notably produced by the recessed portions 10 equallyprovided at the bottom portion 2 x of the cushion member 2.

Note that the formation pattern of the recessed portions 10 illustratedin FIG. 7 has been set forth as a mere example, and the number ofrecessed portions 10 and the formation positions of the recessedportions 10 may be set such that the distance d between adjacent ones ofthe recessed portions 10 is uniform. The present disclosure is notlimited to the above-described pattern. Moreover, the shape of therecessed portion 10 is not limited to the substantially hemisphericalshape and the substantially oval shape, and may be other shapes (e.g., arectangular cylindrical shape).

In an embodiment, each air cell 20 is a bag body made of a materialcapable of suitable stretching, such as a resin material including,e.g., polyethylene and polyurethane. The air cell 20 is configured toexpand by injection of compressed air and to contract by discharge ofthe injected air. Moreover, the air cell 20 of the present embodiment isa bag body with a two-tiered structure as illustrated in FIG. 2.

More specifically, the air cell 20 of the present embodiment includestwo expandable portions vertically arranged to sandwich a narrowedportion 23 equivalent to a dividing portion. Of two expandable portions,an upper expandable portion 21 positioned on an upper side is a biconvexbag body configured to expand such that both of upper and lower endsthereof protrude by injection of compressed air. A lower expandableportion 22 positioned on a lower side has a size slightly larger thanthat of the upper expandable portion 21, and is a biconvex bag bodysimilar to the upper expandable portion 21.

The inside of the upper expandable portion 21 and the inside of thelower expandable portion 22 communicate with each other. Moreover, alower end portion of the lower expandable portion 22 has a compressedair injection port 24. When compressed air is supplied into the lowerexpandable portion 22 through the injection port 24, the lowerexpandable portion 22 expands, and then, the upper expandable portion 21expands. In this state, the upper expandable portion 21 and the lowerexpandable portion 22 expand along an upper-to-lower direction, i.e.,the direction in which two expandable portions are arranged. Note thatthe configuration in which the upper expandable portion 21 and the lowerexpandable portion 22 as two expandable portions are vertically arrangedhas been described as an example. However, in the present disclosure,the number of expandable portions is not limited, and it may beconfigured that two or more expandable portions are arranged.

In the present embodiment, the air cells 20 are attached to the bottomportion 2 x of the cushion member 2. More specifically, the air cells 20are arranged respectively in the recessed portions 10 provided at thebottom portion 2 x of the hip support portions 2 a, 2 b of the cushionmember 2. The arrangement positions of the air cells 20 at the cushionmember 2 is described below with reference to FIG. 8. FIG. 8 is a bottomview of the arrangement positions of the air cells 20, the air supplypump 31, and the valve unit 32 at the cushion member 2.

At the bottom portion 2 x of the front hip support portion 2 a of thecushion member 2, the recessed portions 10 are provided symmetrically asillustrated in FIG. 8. These recessed portions 10 are divided intorecessed portions 10 provided in a region positioned on the front sidewith respect to the crotch position of the passenger at the front hipsupport portion 2 a (hereinafter referred to as “front recessed portions10”) and recessed portions 10 provided in a region positioned rightbelow the crotch, hip, and thighs of the passenger at the hip supportportion 2 a (hereinafter referred to as “back recessed portions 10”).Note that in FIG. 8, the front recessed portions 10 of the recessedportions 10 provided at the front hip support portion 2 a are indicatedby white circles, and the back recessed portions 10 are indicated bycircles with a dot pattern.

In the present embodiment, the air cells 20 are arranged respectively inthe back recessed portions 10 of the recessed portions 10 provided atthe front hip support portion 2 a. Specifically, the back recessedportions 10 include a recessed portion 10 (a recessed portion 10indicated by a reference character “A” in FIG. 8) positioned at a centerportion of the cushion member 2 in the width direction, recessedportions 10 (recessed portions 10 indicated by reference characters “B,”“C,” “D,” and “E” in FIG. 8) arranged around the recessed portion 10indicated by A in a substantially rectangular pattern, and recessedportions (recessed portions 10 indicated by reference characters “F” and“G” in FIG. 8) positioned respectively at end portions of the cushionmember 2 in the width direction. The single air cell 20 is arrangedinside each of these recessed portions 10.

As described above, in the present embodiment, the air cells 20 arerespectively arranged only in the back recessed portions 10 of the frontand back recessed portions 10. Note that the present disclosure is notlimited to such a configuration, and the air cells 20 may be alsoarranged respectively in the front recessed portions 10.

Each of the back recessed portions 10 is, as described above, disposedsuch that a distance between adjacent ones of the recessed portions 10is uniform. Thus, the air cells 20 arranged respectively in the backrecessed portions 10 are also arranged such that a distance betweenadjacent ones of the air cells 20 is uniform.

The above-described arrangement pattern of the air cells 20 at the fronthip support portion 2 a is substantially similar to that of the aircells 20 at the back hip support portion 2 b. Specifically, the recessedportions 10 are also provided symmetrically at the bottom portion 2 x ofthe back hip support portion 2 b. These recessed portions 10 are dividedinto front recessed portions 10 (recessed portions 10 indicated by whitecircles in FIG. 8) and back recessed portions 10 (recessed portions 10indicated by circles with a dot pattern in FIG. 8). The air cells 20 arerespectively arranged only in the back recessed portions 10 of the frontand back recessed portions 10. Note that the present disclosure is notlimited to such a configuration, and the air cells 20 may be alsoarranged respectively in the front recessed portions 10.

Next, operation of the air cell 20 in the recessed portion 10 isdescribed with reference to FIG. 9. FIG. 9 is a schematiccross-sectional view for describing operation of the air cell 20. Asillustrated in FIG. 9, the air cell 20 is disposed in the recessedportion 10 such that two expandable portions are arranged along theupper-to-lower direction (i.e., the thickness direction of the vehicleseat 1). Thus, each air cell 20 expands/contracts along the thicknessdirection of the vehicle seat 1 in a corresponding one of the recessedportions 10. The “corresponding one of the recessed portions 10” foreach air cell 20 is one, in which such an air cell 20 is disposed, ofthe recessed portions 10 formed at the bottom portion 2 x of the cushionmember 2.

On the other hand, the recessed portion 10 is formed to have aslightly-larger size than that of the air cell 20 in a maximum expansionstate. Thus, each air cell 20 expands/contracts in a corresponding oneof the recessed portions 10 as illustrated in FIG. 9, and slightlycontacts an upper end (the ceiling) of a corresponding one of therecessed portions 10 when the air cell 20 expands to the maximum extent.

As described above, each air cell 20 expands in a corresponding one ofthe recessed portions 10, and is housed in such a recessed portion 10even when the air cell 20 expands to the maximum extent. Thus, when theair cell 20 expands, the cushion member 2 (specifically, a portion ofthe cushion member 2 at the periphery of a corresponding one of therecessed portions 10) is not pushed out by the air cell 20. That is, inthe present embodiment, each air cell 20 expands/contracts withoutproviding influence on the outer shape (specifically, the shape of aseat seating surface) of the vehicle seat 1.

In the present embodiment, the hardness of the vehicle seat 1 can beadjusted by expansion/contraction operation of each air cell 20. Morespecifically, the expansion pressure of each air cell 20 is adjusted sothat the hardness of a portion of the vehicle seat 1 provided with suchan air cell 20 (in other words, a portion provided with the recessedportion 10) can be freely changed. With this configuration, the vehicleseat 1 provides a favorable ride quality (a favorable seating feeling)to the passenger(s) while ensuring a suitable level of hardness. Sincethe suitable level of hardness is ensured, sinking (elasticdeterioration) of the seat caused due to continuous application of apassenger's seating pressure for a long period of time can be reduced.

Note that in the present embodiment, each air cell 20 expands/contracts,as described above, along the thickness direction of the vehicle seat 1in a corresponding one of the recessed portions 10. With suchexpansion/contraction operation of the air cell 20, the hardness of thevehicle seat 1 can be effectively adjusted.

Moreover, in the present embodiment, the air cells 20 are equallyarranged at the bottom portion 2 x of the cushion member 2. With thisconfiguration, the hardness of the vehicle seat 1 can be adjusted with afavorable balance. Further, in the present embodiment, the air cells 20can separately expand/contact. With this configuration, the hardness canbe locally adjusted for each portion (for example, for each region ofthe hip support portions 2 a, 2 b) of the cushion member 2. As a result,a higher-hardness (or a lower-hardness) portion of the cushion member 2can be switched depending the situation.

Note that in the present embodiment, the air cells 20 are separated fromeach other. Moreover, in order to expand each air cell 20, compressedair is supplied separately to the air cells 20. Note that the presentdisclosure is not limited to such a configuration, and as illustrated inFIG. 10, an air cell group 26 including some air cells 20 (five aircells 20 in FIG. 10) which are included in the air cells 20 arranged atthe cushion member 2 and which are coupled together may be used tocollectively supply air to each air cell 20 of the air cell group 26.FIG. 10 is a schematic plan view of the above-described air cell group26 as a variation of the air cells 20, and is a schematic plan view ofthe air cell group 26.

The configuration of the air cell group 26 is described with referenceto FIG. 10. In the air cell group 26, one of the air cells 20(specifically, the air cell 20 positioned at the center) is coupled tothe other air cells 20 (specifically, the air cells 20 surrounding thecenter air cell 20) through communication portions 25. The communicationportion 25 is a portion provided for communication among internal spacesof the air cells 20. That is, the internal space of the center air cell20 and the internal spaces of other air cells 20 communicate with eachother through the communication portions 25.

In the air cell group 26 configured as described above, when compressedair is supplied to one of the air cells 20, the compressed air issupplied to all of the air cells 20 of the air cell group 26 through thecommunication portions 25. As a result, all of the air cells 20 of theair cell group 26 can be collectively expanded. Moreover, according tothe above-described configuration, the coupled air cells 20 can becollectively handled. Further, the process for attaching the air cells20 can be further facilitated.

As described above, when compressed air is supplied to the air cells 20,the compressed air may be supplied separately to the air cells 20, ormay be supplied collectively to a group unit of the air cells 20 such asthe above-described air cell group 26.

The fluid supply mechanism 30 is configured to supply compressed air toeach air cell 20. Moreover, in the present embodiment, the fluid supplymechanism 30 is capable of supplying compressed air to at least one ofthe air cells 20 to expand only such air cells 20. Further, the fluidsupply mechanism 30 is capable of switching a compressed air supplydestination to change the air cells 20 to be expanded. A detailedconfiguration of the fluid supply mechanism 30 is described below withreference to FIGS. 3, 4, and 8.

A mechanical configuration of the fluid supply mechanism 30 isdescribed. The fluid supply mechanism 30 includes the air supply pump31, the valve unit 32, and the tubes 33 as illustrated in FIG. 4.Moreover, the fluid supply mechanism 30 includes, as control systemunits, an electronic control unit (ECU) 34 and a sensor 35. Althoughdetails are described below, the fluid supply mechanism 30 includes themountain pass road switch 36 configured to transmit, to the ECU 34, asignal for bringing a state suitable when the motorcycle travels on amountain pass road.

The air supply pump 31 is a compressed air generation device configuredto generate compressed air, and includes a compact air pump. The valveunit 32 is equivalent to a switching device, and operates to switch thesupply destination of the compressed air generated by the air supplypump 31. Specifically, the valve unit 32 has a plurality of compressedair discharge ports. Moreover, an electromagnetic valve (not shown) isprovided in the valve unit 32. The valve unit 32 operates to switch theelectromagnetic valves ON or OFF to switch one(s) of the discharge portsthrough which compressed air is actually discharged.

The tubes 33 are connected respectively into the discharge ports asillustrated in FIG. 4. Each tube 33 is equivalent to a supply pathformation member, and forms a compressed air supply path. Moreover, eachtube 33 is connected to the compressed air injection port 24 of acorresponding one of the air cells 20. Thus, when the valve unit 32switches the discharge port(s) through which compressed air is actuallydischarged, the compressed air supply destination (i.e., the air cells20 to which compressed air is sent) is switched.

Note that in the present embodiment, the air supply pump 31 and thevalve unit 32 are, as in the air cells 20, attached to the bottomportion 2 x of the cushion member 2. The arrangement positions of theair supply pump 31 and the valve unit 32 is described. As illustrated inFIG. 8, in the present embodiment, the air supply pump 31 and the valveunit 32 are attached to the bottom portion 2 x of the non-supportingportion 2 c of the cushion member 2. That is, in the present embodiment,the air supply pump 31 and the valve unit 32 are arranged at positionsdifferent from the seating portions 1 a, 1 b in the vehicle seat 1. Withsuch arrangement positions, influence of the above-described devices onthe ride quality can be reduced.

The ECU 34 is equivalent to a control device, and is configured tocontrol ON/OFF of the air supply pump 31 and to control the valve unit32 to switch the compressed air supply destination. That is, the ECU 34controls the valve unit 32 to switch ones, which are to be actuallyexpanded, of the air cells 20.

Moreover, the ECU 34 of the present embodiment controls the valve unit32 according to the output signal of the sensor 35 or the mountain passroad switch 36. The sensor 35 is a sensor configured to output a signalcorresponding to a traveling condition of the motorcycle on which thevehicle seat 1 is mounted. Specifically, the sensor 35 of the presentembodiment is configured to detect a location where the motorcycle iscurrently traveling and to output a signal corresponding to a detectionresult. More specifically, the sensor 35 outputs a first signal(hereinafter referred to as a “city traveling signal”) when themotorcycle is traveling around a city, and outputs a second signal(hereinafter referred to as a “freeway traveling signal”) when themotorcycle is traveling along a freeway.

Note that the above-described sensor 35 includes, for example, an imagesensor, a speed sensor, or an acceleration sensor, but may be set tohave other suitable configurations as long as the sensor 35 can detectthe traveling location of the motorcycle.

The mountain pass road switch 36 is turned ON/OFF by the passenger inthe situation where the motorcycle is traveling on the mountain passroad. When the passenger turns ON the mountain pass road switch 36, themountain pass road switch 36 outputs a third signal (hereinafterreferred to as a “mountain pass road traveling signal”).

When the ECU 34 receives the output signal from the sensor 35 or themountain pass road switch 36, the ECU 34 analyzes such a signal tospecify the location where the motorcycle is currently traveling. TheECU 34 controls the valve unit 32 according to a traveling locationspecified result. Thus, ones, which are to be actually expanded, of theair cells 20 are automatically switched according to the travelinglocation of the motorcycle. As a result, a higher-hardness (or alower-hardness) portion of the vehicle seat 1 automatically changesdepending on the traveling location of the motorcycle. Further, the aircells 20 to be expanded may be manually switched by the passengeraccording to a passenger's preference.

Operation Example of Seat Apparatus

Next, an operation example of the present device 100 is described.Specifically, the flow of control of the valve unit 32 by the ECU 34,i.e., the flow of hardness adjustment of each portion of the vehicleseat 1 (hereinafter referred to as a “hardness adjustment flow”), isdescribed with reference to FIG. 11. FIG. 11 is a flowchart of thehardness adjustment flow. Note that the case where there is only onepassenger, i.e., the case (hereinafter referred to as a “present case”)where a passenger is seated only on the front seating portion 1 a of thevehicle seat 1, is described as a specific example.

In the hardness adjustment flow of the present case, the air cells 20arranged respectively in the recessed portions 10 (for example, the backrecessed portions 10) at the bottom portion 2 x of the front hip supportportion 2 a of the cushion member 2 are expanded. Specifically, thehardness adjustment flow begins when an ignition switch of themotorcycle is turned ON with the passenger being seated on the vehicleseat 1 (S001). Next, the ECU 34 determines whether or not the travelingspeed (the vehicle speed) of the motorcycle is 0 km/h (S002), and whensuch a speed is 0 km/h, the air supply pump 31 and the valve unit 32 arecontrolled such that all of the air cells 20 arranged respectively inthe back recessed portions 10 are contracted (S003).

On the other hand, when the vehicle speed reaches equal to or greaterthan a predetermined value (S004), the ECU 34 turns ON the air supplypump 31, and controls the valve unit 32 to supply compressed air to allof the air cells 20 arranged respectively in the back recessed portions10. In this manner, all of the air cells 20 arranged respectively in theback recessed portions 10 gradually expand to a predetermined pressure(S005).

Subsequently, the ECU 34 cooperates with the sensor 35 to monitor thetraveling location of the motorcycle, and controls the valve unit 32according to the traveling location. Specifically, e.g., the ECU 34compares the traveling speed detected from the sensor 35 with athreshold stored in a memory 34 a of the ECU 34 (S006). There are twotypes of thresholds stored in the memory 34 a, and one of the thresholdsis a threshold used for determining whether or not the motorcycle istraveling around the city, i.e., a city traveling threshold. The otherthreshold is a threshold used for determining whether or not themotorcycle is traveling along the freeway, i.e., a freeway travelingthreshold. These two thresholds are preset values, and examples thereofinclude the city traveling threshold set within a range of 10 to 60 kmper hour, particularly 30 km per hour in the present embodiment.Moreover, the freeway traveling threshold is set within a range of 60 to10 km per hour, particularly 70 km per hour in the present embodiment.Note that the city traveling threshold and the freeway travelingthreshold are not limited to the above-described values, and can be setat other suitable values.

When the traveling speed reaches equal to or greater than the citytraveling threshold by the signal obtained from the sensor 35, the ECU34 controls the valve unit 32 in a first mode (S007). The “first mode”described herein is the following mode as illustrated in FIG. 12: of theair cells 20 arranged respectively in the back recessed portions 10, theair cell 20 positioned at the center of the seat in the width directionand the air cells 20 surrounding such a center air cell 20 are expandedand the air cells 20 positioned at seat end portions in the widthdirection are not expanded. FIG. 12 is a bottom view for describing thefirst mode. Note that in FIG. 12 and FIGS. 13 and 14 as described below,the air cell 20 to be expanded is indicated by a circle having a hatchpattern.

As described above, while the motorcycle is traveling around the city,the ECU 34 controls the valve unit 32 to expand the air cells 20 in thefirst mode. During such a period, the hardness of the end portions ofthe vehicle seat 1 in the width direction, i.e., the hardness of aportion of the vehicle seat 1 on which the thighs of the passenger areplaced, does not increase, and can relatively easily bend. This reflectsthat ground accessibility (easy grounding of feet at the time ofstoppage) is more emphasized while the motorcycle is traveling aroundthe city and that the end portions of the cushion member 2 in the widthdirection need to easily bend to ensure the ground accessibility.

On the other hand, in comparison between the traveling speed detectedfrom the sensor 35 and each threshold stored in the memory 34 a of theECU 34 (S008), when the traveling speed reaches a value equal to orgreater than the freeway traveling threshold by the signal obtained fromthe sensor 35, the ECU 34 controls the valve unit 32 in a second mode(S009). The “second mode” described herein is, as illustrated in FIG.13, a mode in which all of the air cells 20 arranged respectively in theback recessed portions 10 are expanded. FIG. 13 is a bottom view fordescribing the second mode.

As described above, while the motorcycle is traveling along the freeway,the ECU 34 controls the valve unit 32 to expand the air cells 20 in thesecond mode. During such a period, the hardness of each portion of thefront seating portion 1 a increases. This reflects that while themotorcycle is traveling along the freeway, the vehicle seat 1 (forexample, the cushion member 2) continuously receives the seatingpressure from the passenger for a long period of time, and lowering ofthe elasticity of the cushion member 2 due to such seating pressureneeds to be suppressed.

When the passenger turns ON the mountain pass road switch 36 while themotorcycle is traveling on the mountain pass road (S010), the ECU 34controls the valve unit 32 in a third mode by the signal obtained fromthe mountain pass road switch 36 (S011). The “third mode” describedherein is the following mode as illustrated in FIG. 14: of the air cells20 arranged respectively in the back recessed portions 10, the air cells20 positioned respectively at the seat end portions in the widthdirection are expanded and the air cell 20 positioned at the center ofthe seat in the width direction and the air cells 20 surrounding such acenter air cell 20 are not expanded. FIG. 14 is a bottom view fordescribing the third mode.

As described above, while the motorcycle is traveling on the mountainpass road, the ECU 34 controls the valve unit 32 to expand the air cells20 in the third mode. During such a period, the hardness of the endportions of the vehicle seat 1 in the width direction, i.e., thehardness of the portion of the vehicle seat 1 on which the thighs of thepassenger are placed, increases. On the other hand, the hardness of acenter portion of the vehicle seat 1 in the width direction, i.e., thehardness of a portion of the vehicle seat 1 on which the hip of thepassenger is placed, does not increase, and is held in arelatively-easily bendable state. This reflects that while themotorcycle is traveling on the mountain pass road, when the motorcyclereaches a curved road and the passenger performs a cornering operation,the hardness of each seat portion is set such that the corneringoperation is easily performed. More specifically, when the passengerperforms the cornering operation, a seating posture is stabilized aslong as the hip of the passenger sinks in the seat and the thighs of thepassenger are lifted. This allows the passenger to more easily performthe cornering operation.

Monitoring of the traveling location, setting of the control modeaccording to the traveling location, and control of the valve unit 32based on the set mode as described above are repeated until the ignitionswitch is turned OFF. When the ignition switch is turned OFF (S012), theECU 34 turns OFF the air supply pump 31. Accordingly, the compressed airsealed in the expanded air cells 20 is discharged. At this point, thehardness adjustment flow ends.

As described above, in the present embodiment, the hardness of eachportion of the seating portion 1 a of the vehicle seat 1 automaticallychanges according to the traveling location of the motorcycle. Thus, ahardness balance in the seating portion 1 a can be optimized to thecontents suitable for the traveling location.

Variation of Seating Device of the Present Disclosure

Another embodiment (hereinafter referred to as a “variation”) of theseating device of the present disclosure is described below withreference to FIGS. 15 to 20. FIG. 15 is a schematic view of a bottomportion of a cushion member 102 of the variation and each type ofequipment disposed on the bottom portion. Note that in FIG. 15, abelow-described cover member 140 is omitted for the sake of illustrationof equipment arrangement. FIG. 16 is a plan view of a below-describedair cell unit 120, and FIG. 17 is an exploded, perspective view of theair cell unit 120. FIGS. 18A, 18B, and 18C are side, schematic views ofassembly steps of the air cell unit 120. Note that an assembly state ofthe air cell unit 120 transitions in the order of FIGS. 18A, 18B, and18C. FIG. 19A is an enlarged, partial schematic view of a region X ofFIG. 16. FIG. 19B is a schematic cross-sectional view along an X-X lineof FIG. 19A. FIG. 20 is a cross-sectional view of a vehicle seat 101 ofthe variation illustrated in FIG. 15, specifically a cross-sectionalview along an A-A line of FIG. 15. Note that in FIG. 20, the thicknessdirection of the vehicle seat 101 is indicated by an arrow.

A seating device (hereinafter referred to as a “second seating device100X”) of the variation is similar to the above-described seating device(the present device 100) in terms of a basic configuration and operationof each section of the device. However, the second seating device 100Xis different from the above-described seating device in terms of an aircell configuration and a cushion member configuration of the vehicleseat. Differences between the second seating device 100X and the presentdevice 100 are mainly described below.

As illustrated in FIG. 15, the cushion member 102 of the vehicle seat101 at the second seating device 100X is divided into a portion forminga hip support portion 102 a at a seating portion on a seat front sideand a portion provided with a hip support portion 102 b at a seatingportion on a seat back side. A middle portion of the cushion member 102,specifically a portion sandwiched between the front and back hip supportportions 102 a, 102 b, forms an inclined portion 102 c. As illustratedin FIG. 20, the inclined portion 102 c is a portion of the cushionmember 102 inclining with respect to the thickness direction of thevehicle seat 101 (in other words, the upper-to-lower direction of thevehicle seat 101). Note that in the present variation, the inclinedportion 102 c inclines to be positioned lower toward the front side.

In the present variation, air cells and a fluid supply mechanism 30 arearranged on a bottom portion of the cushion member 102 as illustrated inFIG. 15. Specifically, a plurality of recessed portions 10 for housingthe air cells are formed at the bottom portion of each of the front andback hip support portions 102 a, 102 b of the cushion member 102. At thebottom portion of the front hip support portion 102 a, theabove-described recessed portions 10 are used such that air cells 121,122 of the air cell unit 120 are arranged respectively in the recessedportions 10.

Of the bottom portion of the back hip support portion 102 b, a portionadjacent to the inclined portion 102 c is recessed to form a space. Asillustrated in FIG. 15, an air supply pump 31 and a valve unit 32 of thefluid supply mechanism 30 are arranged in the space. That is, a housingspace 103 formed by a recessed portion of the bottom portion of thecushion member 102 is provided at the bottom portion of the cushionmember 102, and the air supply pump 31 and the valve unit 32 are housedin the housing space 103. The air supply pump 31 and the valve unit 32as described herein are equivalent to electric equipment, and power issupplied from a not-shown power source such that the air supply pump 31and the valve unit 32 operate to supply compressed air to each air cell.

Of the bottom portion of the inclined portion 102 c, a portion adjacentto the back hip support portion 102 b is recessed to form a cavity 104.The cavity 104 is formed as a space continuous to the above-describedhousing space 103. That is, the housing space 103 and the cavity 104 arecontinuous to each other as a single space, and form a substantiallyrectangular space when viewed from a bottom side of the cushion member102.

As illustrated in FIG. 20, one end of the above-described recessed spaceis an opening, and such an opening is disposed to face a side close to abottom plate 3. Further, at least a portion of the opening is coveredwith the cover member 140 as illustrated in FIG. 20. The cover member140 is configured to control entering of foreign substances, rainwater,etc. into the housing space 103, and is made of a waterproof leathermaterial, for example.

In the variation, the cover member 140 covers at least the portion ofthe opening of the housing space 103, and in particular, coverssubstantially the entirety of the opening of the housing space 103. Onthe other hand, a portion of an opening of the cavity 104 continuous tothe housing space, specifically a portion apart from the housing space103, is an opening not covered with the cover member 140. As justdescribed, in the variation, the cover member 140 covers the opening ofthe housing space 103 in the state in which at least the portion of theopening of the cavity 104 is opened. With this configuration,ventilation to the housing space 103 can be ensured while adherence offoreign substances, rainwater, etc. to the air supply pump 31 and thevalve unit 32 can be reduced.

Even if rainwater enters the housing space 103, such rainwater can beproperly discharged through the uncovered portion of the opening of thecavity 104. That is, the cavity 104 is formed at a portion of the bottomportion of the cushion member 102 positioned at the inclined portion 102c. Thus, as long as the portion of the opening of the cavity 104 isopened, rainwater etc. entering the housing space 103 flows (downward)toward the uncovered portion of the opening, and eventually, isdischarged through such a portion. Further, since the portion of theopening of the cavity 104 is opened, influence of heat emitted from anengine (not shown) positioned below the vehicle seat 101 can be reduced.

Next, the air cell unit utilized in the variation is described. The aircell unit 120 is configured such that the air cells 121, 122 arranged atthe portion positioned at the front hip support portion 102 a areintegrated together. The configuration of the air cell unit 120 isdescribed with reference to FIG. 16. As illustrated in FIG. 16, the aircell unit 120 includes an air cell group having five air cells 121arranged in an X-shape, and a pair of right and left air cells 122arranged respectively on both sides of the air cell group. As in the aircell 20 (e.g., the air cell 20 illustrated in FIG. 2) of theabove-described embodiment, each of the air cells 121, 122 has atwo-tiered structure with upper and lower expandable portions.

The air cell group including five air cells 121 is disposed at a centerportion of the front hip support portion 102 a in the width direction.As in the above-described air cell group 26 illustrated in FIG. 10, theair cell group is configured such that the center air cell 121 iscoupled with other air cells 121 (specifically, the air cells 121surrounding the center air cell 121). Note that the air cells 121 arecoupled together via below-described flow path formation members 124.That is, an internal space of the center air cell 121 and internalspaces of other air cells 121 communicate with each other through a flowpath formed by the flow path formation members 124. Thus, whencompressed air is supplied to the center air cell 121, each air cell 121of the air cell group expands.

Each of the pair of right and left air cells 122 has a substantiallyfan-shaped outer shape, and these air cells 122 are arrangedrespectively at end portions of the front hip support portion 102 a inthe width direction. Moreover, the right and left air cells 122 in apair are coupled together through a flow path formation member 124described below. That is, an internal space of the air cell 122 on oneend side (the left side) in the width direction and an internal space ofthe air cell 122 on the other end side (the right side) in the widthdirection communicate with each other through the flow path formed bythe flow path formation member 124. Thus, when compressed air issupplied to the pair of right and left air cells 122, both air cells 122simultaneously expand.

The air cell unit 120 has the compressed air flow paths. That is, in thevariation, the air cell unit 120 includes the flow path formationmembers 124. The flow paths formed by the flow path formation members124 extend toward the air cells 121, 122 of the air cell unit 120. Asillustrated in FIG. 16, a tip end portion of a tube 33 is inserted intoa tip end portion (an upstream end portion) of the flow path formationmember 124, and a terminal end portion (a downstream end portion) of theflow path formation member 124 is connected to a suction/discharge portof each of the air cells 121, 122.

Note that in the case illustrated in FIG. 16, the flow path formationmembers 124 for supplying compressed air to the air cell group includingfive air cells 121 and the flow path formation member 124 for the pairof right and left air cells 122 are separately provided. That is, twolines of the flow path formation members 124 are provided, and insertionports 125 into each of which the tip end portion of the tube 33 isinserted are provided separately for the lines. Note that the presentdisclosure is not limited to such a configuration, and theabove-described two lines of the flow path formation members 124 may beintegrated together (i.e., a common line may be shared).

The flow path formation member 124 described herein is made of abendable material, specifically a polyurethane sheet or a resin filmsheet made of, e.g., polyvinyl chloride. Further, in the configurationillustrated in FIG. 16, the air cells 121, 122 and the flow pathformation members 124 are integrally made of a common material.Specifically, the air cell unit 120 is configured such that four typesof resin film sheets (specifically, a first sheet 201, a second sheet202, a third sheet 203, and a fourth sheet 204) having different sizesas illustrated in FIG. 17 are stacked on each other. The above-describedfour types of resin films are stacked on each other to mold the air cellunit 120, and as a result, the air cells 121, 122 and the flow pathformation members 124 are integrally molded.

Specifically, each of the air cells 121, 122 of the air cell unit 120 isformed using all of the above-described four types of resin films. Ofeach of the air cells 121, 122 each including the two-tiered upper andlower expandable portions, the upper expandable portion is formed of thefirst sheet 201 forming the uppermost layer and the second sheet 202forming the second layer from the top, and the lower expandable portionis formed of the third sheet 203 forming the third layer from the topand the fourth sheet 204 forming the lowermost layer.

The assembly steps of the air cell unit 120 (in particular, formationsteps of the air cells 121, 122) is described with reference to FIGS.18A to 18C. In assembly of the air cell unit 120, the third sheet 203formed with a relatively-large flat surface is first set on a mold. Atthis point, the third sheet 203 is cut along the outer shape of the aircell unit 120, and specifically, is cut in a substantially isoscelestrapezoidal shape as illustrated in FIG. 17.

Subsequently, the second sheet 202 is disposed on the third sheet 203set on the mold. More specifically, the second sheet 202 is cut alongthe outer shape of each of the air cells 121, 122, and is disposed at apredetermined portion of an upper surface of the third sheet 203 set onthe mold. At this point, the pieces of the second sheet 202 in theabove-described shapes are, as illustrated in FIG. 18A, arrangedcorresponding respectively to the formation positions of the air cells121, 122 by position control using guides 212. In other words, portionsof the third sheet 203 corresponding respectively to the formationpositions of the air cells 121, 122 are provided with air holes.Moreover, each piece of the second sheet 202 cut into a correspondingone of the above-described shapes has an air hole. Then, the secondsheet 202 is disposed at such a position that each air hole of thesecond sheet 202 communicates with a corresponding one of the air holesof the third sheet 203.

Then, the second sheet 202 is welded to the third sheet 203 with a core211 being interposed between an outer edge portion of the second sheet202 and the third sheet 203. More specifically, welding tools (welders)210 for thermal welding are pressed against the periphery of each airhole of the second sheet 202, and in this manner, a portion around suchan air hole of the second sheet 202 is thermally welded to a portionaround a corresponding one of the air holes of the third sheet 203.

Subsequently, the first sheet 201 is placed on the second sheet 202. Atthis point, the first sheet 201 is cut to have the same outer shape asthat of the second sheet 202. The first sheet 201 is thermally welded tothe second sheet 202 with the first sheet 201 being placed on the secondsheet 202. More specifically, in the state in which an edge portion ofeach piece of the first sheet 201 cut into the above-described shapeoverlaps with an edge portion of a corresponding one of the pieces ofthe second sheet 202, the welding tools 210 are pressed against theseedge portions to thermal weld the edge portions together as illustratedin FIG. 18B.

Subsequently, the fourth sheet 204 is set below the third sheet 203, andthe third sheet 203 and the fourth sheet 204 are thermally weldedtogether. More specifically, as in the third sheet 203, the fourth sheet204 is cut along the outer shape of the air cell unit 120. Then, in thestate in which the fourth sheet 204 at the position below the thirdsheet 203 overlaps with the third sheet 203, predetermined portions ofthese sheets are thermally welded together. More specifically, thewelding tools 210 are pressed against portions positioned at an outeredge of each of the air cells 121, 122 (in particular, an outer edge ofthe lower expandable portion), and such portions are thermally weldedtogether, as illustrated in FIG. 18C.

Note that when the third sheet 203 and the fourth sheet 204 arethermally welded together, thermal welding is performed such thatpredetermined portions of these sheets form the flow path formationmembers 124. More specifically, a portion of the third sheet 203positioned at the flow path is lifted from the fourth sheet 204, andthen, other portions (excluding portions corresponding to the air cells121, 122) than the lifted portion are thermally welded together. In thismanner, the lifted portion of the third sheet 203 and the fourth sheet204 positioned below such a portion form the flow path formation member124.

As described above, in the variation, the flow path formation members124 are simultaneously molded in the process of assembling the air cellunit 120 (in other words, the process of forming the air cells 121,122). Note that portions of the air cell unit 120 other than the aircells 121, 122 and the flow path formation members 124 (specifically,the portion at which the third sheet 203 and the fourth sheet 204 arejoined together) form a sheet-shaped base portion 123.

As described above, the flow path formation members 124 provided in theair cell unit 120 are formed of the resin film sheets, and therefore,are configured to be bendable. In the variation, the air cells 121, 122and the flow path formation members 124 are integrally made of thecommon material. Thus, when the air cells 121, 122 expand, there is alikelihood that such movement is transmitted to the flow path formationmembers 124 to bend the flow path formation members 124 (cause bendingwrinkles), for example. Such bending of the flow path formation members124 might result in clogging of the flow paths. Due to clogging of theflow paths, supply of compressed air to the air cells 121, 122 anddischarging of compressed air from the air cells 121, 122 are notproperly performed.

For these reasons, in the variation, a tubular body 130 is disposed ineach flow path formation member 124 for the purpose of controllingbending of the flow path formation member 124. Specifically, asillustrated in FIG. 16, the tubular body 130 is disposed in each flowpath formation member 124 coupling the center air cell 121 and other aircells 121 together in the air cell group including five air cells 121.Moreover, as illustrated in FIG. 16, the tubular body 130 is disposed inthe flow path formation member 124 extending toward the pair of rightand left air cells 122.

The tubular body 130 is now described. The tubular body 130 is acylindrical pipe piece having a smaller outer diameter than that of theflow path formed by the flow path formation member 124 and made of amaterial (e.g., a resin molded article thicker than the flow pathformation member 124) harder than the material of the flow pathformation member 124. The inside of the tubular body 130 forms a portionof the flow path for compressed air. That is, when reaching thearrangement position of the tubular body 130, compressed air flowingthrough the flow path flows through the inside of the tubular body 130.

Since the tubular body 130 is disposed in the flow path formation member124 as described above, bending of the flow path formation member 124 iscontrolled, and as a result, clogging of the flow path due to bending ofthe flow path formation member 124 can be reduced.

Note that in the variation, at least a portion of the tubular body 130is disposed at a connection portion between the flow path formed by theflow path formation member 124 and the air cell 121, 122 in the flowpath formation member 124, as illustrated in FIG. 19A. For example, thetubular body 130 passes through the suction/discharge port of the aircell 121, 122, and the portion of the tubular body 130 enters the aircell 121, 122. With this arrangement position, the effect of the tubularbody 130 is remarkably produced. That is, the connection portion betweenthe flow path for compressed air and the air cell 121, 122 is a promotesproper expansion/contraction of the air cell 121, 122, and clogging ofthe flow path at such a portion is preferentially avoided. For thisreason, the tubular body 130 is disposed at the above-describedarrangement position, and as a result, can be utilized to effectivelyreduce clogging of the flow path.

Of the flow path formation member 124, a portion (hereinafter referredto as a “tubular body included portion”) in which the tubular body 130is disposed has a cross-sectional structure (a cross-sectional structureintersecting the extension direction of the flow path formation member124) illustrated in FIG. 19B. Specifically, the tubular body includedportion includes a raised portion 124 a and a flat portion 124 b, asillustrated in FIG. 19B. The raised portion 124 a is a portion of thecylindrical tubular body included portion raised in an arc shape along asurface of the cylindrical tubular body 130. The raised portion 124 a ispositioned to face the cushion member 102.

The flat portion 124 b is a portion extending flat and positionedopposite to the raised portion in the tubular body included portion.That is, a portion of the tubular body included portion positionedopposite to the cushion material 102, i.e., a portion facing the bottomplate 3, is not in a shape curved in an arc shape as in the raisedportion 124 a, but is in a flat shape. Thus, the tubular body includedportion receives, at the surface (the flat surface), a load applied fromthe side close to the bottom plate 3. Since the load is received at theflat surface, occurrence of the situation in which the flow pathformation member 124 is damaged (broken) due to the load from the sideclose to the bottom plate 3 can be reduced.

As described above, in the variation, the tubular body 130 is disposedin each flow path formation member 124. In the variation, the tubularbody 130 is inserted into each flow path formation member 124 inassembly of the air cell unit 120. Specifically, at the assembly stepsof the air cell unit 120, the tubular bodies 130 are fixed in advance tothe resin film sheet forming the flow path formation members 124,specifically the third sheet 203. More specifically, as illustrated inFIG. 17, each tubular body 130 is fixed to a corresponding position (forexample, a position at which the flow path formation member 124 isprovided and which is close to the suction/discharge port of the aircell 121, 122) of a lower surface of the third sheet 203.

Note that a material forming the tubular body 130 is the same type ofmaterial (i.e., the material forming the flow path formation member 124)as that of the third sheet 203, in an embodiment. Thus, in thevariation, the tubular bodies 130 are fixed to the lower surface of thethird sheet 203 by thermal welding. In other words, in the state inwhich the air cell unit 120 is completed, the tubular bodies 130 arefixed respectively to the flow path formation members 124 by thermalwelding. With such a configuration, the tubular bodies 130 can be easilyfixed respectively to the flow path formation members 124.

After the tubular bodies 130 have been fixed (thermally welded) to thelower surface of the third sheet 203, the air cell unit 120 is assembledby the above-described steps. Thus, the air cell unit 120 configuredsuch that the tubular bodies 130 are arranged respectively in the flowpath formation members 124 can be easily formed.

Note that a size of the flow path formation member 124 (for example, adiameter of the flow path) may be determined and/or selected, and may bevaried according to location. In response to this, an external diameterand an internal diameter may be properly varied according to theinstallation location. Specifically, it is preferable to set a propersize according to flow rate (i.e., air supply rate) of the compressedair flowing in the tubular bodies 130.

Other Embodiments

In the above-described embodiment, the example of the seat apparatus ofthe present disclosure has been mainly described. However, theabove-described embodiment is for the sake of easy understanding of thepresent disclosure, and does not limit the present disclosure. That is,changes and modifications can be made to the present disclosure withoutdeparting from the gist of the present disclosure, and needless to say,the present disclosure includes equivalents thereof.

In the above-described embodiment, the configuration in which expansionoperation of each air cell 20 is automatically performed according tothe traveling location of the motorcycle has been described, but thepresent disclosure is not limited to such a configuration. For example,an operation section including a button, a switch, etc. may be providedsuch that the ECU 34 expands each air cell 20 with passenger's operationof the operation section as a trigger. Note that by operation of theabove-described operation section, the air cells 20 to be actuallyexpanded may be selected from the air cells 20.

In the above-described embodiment, the case where the ECU 34 mainlycontrols the valve unit 32 according to the traveling location as thetraveling condition of the motorcycle has been described as an example.Note that control may be made according to other traveling conditionsthan the traveling location, and for example, control may be madeaccording to the vehicle speed or a road condition. Alternatively, thevalve unit 32 may be controlled according to other items than thetraveling condition of the motorcycle, and for example, control may bemade according to the shape or type of the body of the passenger or apassenger's request.

In the above-described embodiment, compressed air has been described asan example of fluid, and the air cell 20 configured to expand byinjection of the compressed air has been used. Note that a bag bodycapable of expanding by injection of other types of fluid than thecompressed air, such as types of gas other than air, liquid such aswater, or fluid in the form of gel, may be used instead of the air cell20.

In the above-described embodiment, three patterns illustrated in FIGS.12 to 14 have been described as the example patterns (in other words,the modes in control of the valve unit 32) of the air cells 20 which areincluded in the air cells 20 and which are to be actually expanded. Notethat the expansion patterns of the air cells 20 are not limited to thoseillustrated in FIGS. 12 to 14, but can be freely set.

TABLE OF REFERENCE NUMERALS

-   1 vehicle seat-   1 a, 1 b seating portion-   1 c non-seating portion-   2 cushion member-   2 a, 2 b hip support portion (portion positioned at the seating    portion)-   2 c non-supporting portion (portion different from the seating    portion)-   2X bottom portion-   3 bottom plate-   4 skin material-   10 recessed portion-   20 air cell (bag body)-   21 upper expandable portion (expandable portion)-   22 lower expandable portion (expandable portion)-   23 narrowed portion (dividing portion)-   24 injection port-   25 communication portion-   26 air cell group-   30 fluid supply mechanism-   31 air supply pump (compressed air generation device)-   32 valve unit (switching device)-   33 tube (supply path formation member)-   34 ECU (control device)-   34 a memory-   35 sensor-   36 mountain pass road switch-   100 present apparatus (seat apparatus)-   100X second seat apparatus-   101 vehicle seat-   102 cushion member-   102 a, 102 b hip support portion-   102 c inclined portion-   103 housing space-   104 cavity-   120 air cell unit-   121, 122 air cell (bag body)-   123 sheet-shaped base portion-   124 flow path formation member-   124 a raised portion-   124 b flat portion-   125 insertion port-   130 tubular body-   140 cover member-   201 first sheet-   202 second sheet-   203 third sheet-   204 fourth sheet-   210 welding tool-   211 core-   212 guide

What is claimed is:
 1. A seat apparatus comprising: a vehicle seatincluding a cushion member having a bottom portion with a plurality ofrecessed portions; a plurality of bag bodies configured to expand byinjection of fluid; and a fluid supply mechanism configured to supplythe fluid to the plurality of the bag bodies, wherein at least one ofthe plurality of the recessed portions is provided in a portion of thebottom portion of the cushion member positioned in a seating portion ofthe vehicle seat, the seating portion being a portion of the vehicleseat on which a hip of a passenger is placed, wherein each of theplurality of the bag bodies is expandable in a corresponding one of therecessed portions, and wherein the fluid supply mechanism is configuredto expand at least one bag body of the plurality of the bag bodies bysupplying the fluid thereto and to change the at least one bag body tobe expanded by switching a fluid supply destination.
 2. The seatapparatus according to claim 1, wherein the recessed portions formed atthe portion of the bottom portion of the cushion member positioned atthe seating portion are provided such that a distance between adjacentones of the plurality of the recessed portions is uniform.
 3. The seatapparatus according to claim 1, wherein the each of the plurality of thebag bodies includes two or more expandable portions arranged with adividing portion being interposed therebetween, wherein the plurality ofthe bag bodies are arranged such that a distance between adjacent onesof the plurality of the bag bodies is uniform, and wherein internalspaces of the two or more expandable portions of the each of theplurality of the bag bodies communicate with each other.
 4. The seatapparatus according to claim 1, wherein the each of the plurality of thebag bodies is an air cell, and wherein the air cell is configured toexpand along a thickness direction of the vehicle seat by injection ofcompressed air as the fluid, and to contract in the thickness directionby discharging of the injected compressed air.
 5. The seat apparatusaccording to claim 1, wherein two or more of the plurality of the bagbodies are coupled together, and wherein internal spaces of the two ormore of the plurality of the bag bodies which are coupled togethercommunicate with each other.
 6. The seat apparatus according to claim 1,wherein the fluid supply mechanism includes a switching device operatingto switch the fluid supply destination, a sensor configured to output asignal corresponding to a traveling condition of a vehicle on which thevehicle seat is mounted, and a control device configured to control theswitching device according to the signal output from the sensor, andwherein the control device controls the switching device to switch theat least one bag body to be expanded.
 7. The seat apparatus according toclaim 1, wherein the each of the plurality of the bag bodies is an aircell, wherein the fluid supply mechanism includes a compressed airgeneration device configured to generate the compressed air as thefluid, a supply path formation member forming a supply path of thecompressed air, and a switching device connected to the supply pathformation member and operative to switch the compressed air supplydestination, and wherein the air cell, the compressed air generationdevice, and the switching device are attached to the bottom portion ofthe cushion member.
 8. The seat apparatus according to claim 7, whereinthe compressed air generation device and the switching device areattached to a portion of the bottom portion of the cushion member at aposition different from the seating portion.
 9. The seat apparatusaccording to claim 1, further comprising: a flow path formation memberof which an inner space constitutes a flow path for the fluid to extendtoward the each of the plurality of the bag bodies, the flow pathformation member being made of a bendable material; and a tubular bodydisposed in the flow path formation member and that forms, on an innerside thereof, a portion of the flow path, wherein the tubular body ismade of a material harder than that of the flow path formation member.10. The seat apparatus according to claim 9, wherein the flow path isconnected to the each of the plurality of the bag bodies, and wherein atleast a portion of the tubular body is, in the inner space of the flowpath formation member, disposed at a connection portion between the flowpath and the each of the plurality of the bag bodies.
 11. The seatapparatus according to claim 9, wherein a portion of the flow pathformation member in which the tubular body is disposed includes a raisedportion raised along a surface of the tubular body and positioned toface the cushion member, and a flat portion positioned opposite to theraised portion and extending flat.
 12. The seat apparatus according toclaim 9, wherein the tubular body is made of a resin material which is asame material as that of the flow path formation member, and is weldedto the flow path formation member.
 13. The seat apparatus according toclaim 9, wherein the each of the plurality of the bag bodies and theflow path formation member are integrally made of a common material. 14.The seat apparatus according to claim 1, wherein the fluid supplymechanism includes electric equipment operative to supply the fluid,wherein the bottom portion of the cushion member is provided with ahousing space of the electric equipment, the housing space being formedby recessing a portion of the bottom portion, and wherein a cover memberconfigured to cover at least a portion of an opening of the housingspace is further provided.
 15. The seat apparatus according to claim 14,wherein the cushion member includes an inclined portion inclining withrespect to a thickness direction of the vehicle seat, wherein the bottomportion at the inclined portion is provided with a cavity, the cavitybeing formed by recessing a portion of the bottom portion, wherein thecavity is continuous to the housing space, and wherein the cover membercovers the opening of the housing space in a state in which at least aportion of an opening of the cavity opens.